feat(cover): request chatgpt to fill out template

backend/controllers/cover/cover.go

@@ -3,6 +3,7 @@ package cover
 import (
 	"backend/models/template"
 	"backend/utils"
+	"backend/utils/chatgpt"
 	"backend/utils/jwt"
 	res "backend/utils/responses"
 	"net/http"
@@ -43,9 +44,20 @@ func Post(c *gin.Context) {
 		return
 	}
 
-	// Call chat and ask for cover letter nicely
+	// Check if template exists
+	if len(templates) == 0 {
+		res.Error(c, "Template not found", http.StatusNotFound)
+		return
+	}
 
-	res.Success(c, templates)
+	// Call chat and ask for cover letter nicely
+	coverLetter, err := chatgpt.GenerateCoverLetter(templates[0].Template, data.Application)
+	if err != nil {
+		res.Error(c, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	res.Success(c, coverLetter)
 }
 
 func Put(c *gin.Context) {

backend/utils/chatgpt/chatgpt.go

@@ -1 +1,86 @@
 package chatgpt
+
+import (
+	"backend/config"
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+type ChatRequest struct {
+	Model    string        `json:"model"`
+	Messages []ChatMessage `json:"messages"`
+}
+
+type ChatMessage struct {
+	Role    string `json:"role"`
+	Content string `json:"content"`
+}
+
+func GenerateCoverLetter(templateHTML string, jobHTML string) (string, error) {
+	apiKey := config.Env["CHATGPT_KEY"]
+	if apiKey == "" {
+		return "", errors.New("no API key chat gpt provided")
+	}
+
+	payload := ChatRequest{
+		Model: "gpt-4o", // o4-mini
+		Messages: []ChatMessage{
+			{
+				Role:    "system",
+				Content: `You are a helpful assistant that fills out cover letter templates in HTML format. Replace all <...> tags like <company>, <experience>, etc., with appropriate content based on the job application.`,
+			},
+			{
+				Role: "user",
+				Content: fmt.Sprintf(`Template: 
+%s
+
+Job description:
+%s
+
+Respond with ONLY the filled HTML cover letter.`, templateHTML, jobHTML),
+			},
+		},
+	}
+
+	body, err := json.Marshal(payload)
+	if err != nil {
+		return "", err
+	}
+
+	req, err := http.NewRequest("POST", "https://api.openai.com/v1/chat/completions", bytes.NewBuffer(body))
+	if err != nil {
+		return "", err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", "Bearer "+apiKey)
+
+	client := &http.Client{Timeout: 20 * time.Second}
+	res, err := client.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer res.Body.Close()
+
+	var result struct {
+		Choices []struct {
+			Message struct {
+				Content string `json:"content"`
+			} `json:"message"`
+		} `json:"choices"`
+	}
+
+	if err := json.NewDecoder(res.Body).Decode(&result); err != nil {
+		return "", err
+	}
+
+	if len(result.Choices) == 0 {
+		return "", fmt.Errorf("no response from GPT")
+	}
+
+	return result.Choices[0].Message.Content, nil
+}

backend/utils/checkData.go

@@ -1,8 +1,6 @@
 package utils
 
 import (
-	"fmt"
-
 	"github.com/gin-gonic/gin"
 	"github.com/go-playground/validator/v10"
 )
@@ -10,20 +8,12 @@ import (
 var validate = validator.New()
 
 func BindAndValidate(data any, c *gin.Context) error {
-	fmt.Println("🔍 BindAndValidate called")
-
 	if err := c.ShouldBindJSON(data); err != nil {
-		fmt.Println("❌ Bind error:", err)
 		return err
 	}
 
-	fmt.Println("✅ Bind success:", data)
-
 	if err := validate.Struct(data); err != nil {
-		fmt.Println("❌ Validation error:", err)
 		return err
 	}
-
-	fmt.Println("✅ Validation success")
 	return nil
 }